Electric regulation



Witness w. w. HUNZICKER.

ELECTRIC REGULATION.

APPLICATION FILED, OCT. 6,1919.

, Patented Apr. 18, 1922.

Ema/m UNITED STATES PATENT OFFICE.

WALTER W. HUNZICKER, LAFAYETTE, INDTANA, ASSIGNOR TO THE OHIO BRASS COMPANY, OF MANSFIELD, MASSACHUSETTS, A CORPORATION OF NEW JERSEY.

ELECTRIC REGULATION.

Application filed October 6', 1919. Serial No. 328,725.

T 0 all whom it may concern.

Be it known that I, WALTER W! HUNZICK- ER, a citizen of the United States of America, residing at Lafayette, in the county of Tippecanoe and State of Indiana, have invented certain new and useful Improvements in Electric Regulations, of which the following is a specification. This invention relates to improvements in electric regulation and as it has more particular reference to lighting systems for electric cars, and the like, it will be described in connection with such a system. It is to be understood, however, that the invention is not limited in its use to lighting systems, but that it can be used in connection with any system or electric circuit in which it is essential or desirable-to maintain a certain pr determined voltage across or constant current value in certain arranged circuits.

The particular form of system to which the present invention relates is especially adapted for use in connection with one or more electric circuits which receive power for the various circuits from a common source of supply, as a trolley wire, or line conductor of variable voltage and by inserting a variable resistance in series with such circuit or circuits and automatically operated, I am able to maintain a reasonably uniform predetermined voltage across the circuit or circuits referred to and hence a reasonably constant current as the resistance of such circuits is practically constant.

In operation, when normal conditions prevail, a certain predetermined line voltage to which the circuits are connected is constantly maintained and the various circuits will function properly and effectively and the lights will be maintained at candlepower. Under certain abnormal conditions," however, as when a crowded car is. pulled up a grade the voltage in the main line will drop below normal by reason of the heavy pull of current in the motor circuit to propel the car. ous circuits, as now operated, deficient to some extent but more particularly the lighting circuit, or system, which, upon any considerable drop in voltage becomes very inefiicient and very noticeable.

Myinvention seeks toobviate the above stated objection, which in the present instance is recited in connection with a lighting system for the sake of convenience only,

This drop in voltage renders the vari and has for its primary object the provision of improved means whereby a certain predetermined voltage or current value may be constantly maintained in the electric circuits, and which I will call the lighting circuits, irrespective of any variation or fluctiiation of the voltage in the source of sup- P I Another object ofthis invention is to provide improved meanswhereby a part of the lighting system may be cut out by accident or design without injury to the other part of the system as more fully explained hereinafter. I

A further object is to provide an improved lighting system which will be effective and eflicient in operation and which when once installed does not require further attention other than occasional adjustment.

To the attainment of these ends and the accomplishment of'other new and useful objects, as will appear, the invention consists in apparaus and circuits for carrying out the above objects and having the general mode of operation more fully described, and claimed, and illustrated in the accompanying drawing, It will. of course, be understood that the system illustrated in the drawing, and .the apparatus, may be changed in many ways without departing from the invention and, that the drawing illustrates merely sufficient features of the system to disclose the invention.

According to my invention the lighting system or. circuits receive energy from a main line and is designed to operate on a portion only of the normal line voltage and since I maintain the resistance of such circuits practically constant the current flowing in the circuits will be practically constant if the voltage across such circuits is constant. Since the source of energy is variable, I connect a variable resistancedevice in series with the light circuit or circuits and mechanism is employed embodying mechanically operating means and electricall y operating means for varying the resistance. device upon fluctuation of the line voltage thereby to maintain a practically predetermined constant voltage or current value in the lighting circuit or circuits.

Referring to the diagrammatic View of the drawing, the numeral 1 designates a head-light arranged within a headlight circuit 2 of a car lighting system which receives energy from a trolley wire 3 through a supply conductor at as by means of a trolley pole 5. The lighting system. may be controlled by a suitable switch (3 arranged in the conductor 1 at any convenient point and which. when closed permits passage of current through the headlight circuit 2 and car light circuit 10, to be described hereinailr ter, and thence to ground through the ground wire 7. A suitable resistance 8 may also be provided in series with the headlight 1 it required as may be the case when a low voltage lamp 1 is used.

The lighting circuits are adapted to operate on a portion only of the normal trolley wire voltage and for the purpose of absorbin the balance of the trolley wire Volta to obtain the proper voltage across the circuits and to maintain said voltage and current constant irrespective of trolley wire volt age fluctuations I employ a variable resistance 11, indicated as of the carbon pile type, and which is arranged in series with the supply conductor 1 through which. cn-

ergy is supplied to the lighting circuits. The resistance of the member 11 may be controlled by a mechanism comprising a pivoted lever 12 actuated in one direction by the adjustable spring 13 in such manner as to tend to compress the carbon pile 11 and lower the resistance thereof. The spring tension is controlled by the adjusting screw 13. Secured to the lever 12 at the opposite side of the spring is a core 1 1 of magnetic material surrounded by a solenoid 15 arranged in the present instance in series in the headlight circuit 2 and connected in series with the carbon pile 11. \Vhen current is flowing through the solenoid it moves the core 141 against action of the spring 13 and tends to lessen the pressure of the lever 12 against the carbon pile thereby increasing the resistance thereof.

In carrying out the invention it is necessary to adjust the light circuits 2 and 10 for a certain no anal current value and connect the variable resistance, through which the various lighting circuits are supplied, in series with the source of supply. The solenoid 15 is connected in series with the variable resistance and may be arranged within one of the lighting circuits only, of the lighting system, as for instance in the present embodiment it is shown as in the headlight circuit 2 which consequently carries the controlling current. I so adjust the spring 13 by the adjusting screw 13 that the proper current will flow in the headlight circuit 2, and be held. constant by action of the solenoid which will respond to current or voltage fluctuations. Under normal trolley wire voltage the adjustment between the spring and solenoid is such as to secure a balance when the proper current is flowing in circuit 2, then with a decrease in trolley voltage the solenoid will weaken as less current will iiow in circuit 2 and allow the spring to become ellertive and thus decrease the resistance of the carbon pile to compensate for the drop in line voltage. Then as the trolley voltage becomes normal, or rises, the solenoid strengthens and becomes elfectire over the spring and increases the resistance ot the carbon pile and thus prevents an increase of current or voltage drop across the lighting circuit 2.

In the car light circuit 10 is arranged a series of lamps 16 which may be located in the car. This circuit 10 is preferably arranged in parallel with the head light circuit 2 and is connected to the supply conductor a at approximately the same point as the circuit 2 and is therefore subject to regulation as provided by the variable resistance carbon pile.

Knowing the' resistance of and normal current required in the headlight circuit 2, it is very easy to calculate the potential drop in the circuit 2 and in installing other parallel circuits such as light circuit 10, the re sistance is so adjusted that with the proper current flowing through such circuit the voltage drop across that circuit will equal that across the control or head light circuit 2.

The solenoid 15 is wound to operate as above outlined when the proper amount of current is flowing therethrough to energize the headlight circuit and hence is adapted to maintain a, constant drop in voltage across the lighting circuits by co-acting with the spring 13 to vary the pressure on the carbon pile thereby varying the resistance thereof as hereinbefore described.

It. the headlight circuit should collapse by accident or design, as for instance by burn ing out of the solenoid or headlight, the solenoid would weaken with a consequent increase in current flow in the our light circuit. This current increase would probably result in burning out the car lamps 16 or other injury to the system. To guard against this I provide a protective element or resistance 26 adapted to be automatically thrown in series with the car light circuit incident to the collapse of the headlight or control circuit thereby preventing injury to said circuit. For this purpose a bracket 18 composed of non-magnetic material may be socured to one end of the short core 14: in any suitable manner, as by a set screw 19. A magnetically controlled switch or contactor 20 may be mounted on the bracket and adapted to be maintained in normal solid line position by magnetism of the core under normal operation of the control circuit. In this position of the switch it serves to electrically connect the terminals 21 and 22 of the car light circuit, thus providing for an uninterrupted passage of current from to the proper value, will protect the car light 21 with the terminal 24 of aconductor'25 having arranged therein a suitable resistance and connected to the car lightcircuit or conductor 10 as at 27 Consequently when the switch is in safe positionthe protective resistance 26, which is designed to reduce the current flowing through the lamps l6 circuit from injury. The headlight or control circuit is further arranged so that with theturning oil of the headlight or breakage of the same the regulation of the car light circuit will be sustained by throwing in a resistance equivalent to that of the headlight 1 and resistance 8 and which will re-establish thecontrol circuit. Such resistance 28 is provided and connected at onev end to a terminal 29 and at its other end to the ground wire 7. A switch 30 is inserted in the control circuit .and normally held in the solid line position to electrically connect the terminals 31 and 32 of the control circuit thereby to provide for an uninterrupted flow of currentthrough the headlight to ground. The headilght may be cut out and the regulation of the system maintained by moving the switch to the dotted line position where it operates to electrically connect the terminals 31 and 29 7 thus throwing in the resistance 28 which will maintain the normal current fiow in the control circuit.

Having thus fully described my invention, I do not wish to be limited to the details of construction, arrangements of circuits, nor to the exact mode of operation set forth herein in describing one type of system embodying the elements thereof, for it will be obvious that many changes may be made without departing from the spirit and scope of my invention which is as set forth in the following claims:

I claim 1. In an electric system a plurality of parallel circuits, regulating means comprising a variable resistance unit arranged in series with the circuits for establishing and maintaining a predetermined current flow in each of the parallel circuits irrespective of voltage fluctuation in the source of supply, magnetically operating means in one of the circuits for controlling said regulating means, and auxiliary resistance means adapted to be automatically thrown in series with said regulating means for controlling one of said circuits upon collapse of the circuit wherein said opera ting means is arranged.

v2. An electric system comprising an electric circuit, regulating means comprising a variable resistance unit controlled. by the current fluctuation inthe electric circuitin series therewith, operating means connected in series with the regulating means for controlling said regulating means, a resistance in a normally interrupted circuit adapted to be connected in series with said operating means when said electric circuit is interrupted thereby maintaining the normal flow of current through said operating means, and means for interrupting said electric circuit and connecting said resistance in series with the operating means.

3. In an electric system, an electric circuit, a variable resistance regulating means in series therewith, a control circuit also connected in series with the regulating means, electro-mechanically operating means in the control circuit for varying the resistance of the regulating means with variation of the current in the control circuit and means in said electric circuit operated by the electro-mechanical means for controlling said electric circuit.

4. In an electric system, a control circuit, regulating means connected in serles therewith, electrically operating meansfor conmeans, a circuitconnected to and paralleling the control circuit and receiving energy therefrom, a protective resistance normally in open circuit and connected to said paralleling circuit, and means arranged in the paralleling. circuit and operated by the electrically operating means for automatically connecting said protective resistance in. series therewith upon collapse of the control circuitr 5. The combination of a control circuit, a variable resistance regulating means in series therewith, electrically operating means for controlling said regulating means con nected in the control circuit and in series with the regulating means, means for adjusting said operating means, a parallel circuit connected to the control circuit and reresistance in series with said parallel circuit upon collapse of the control circuit.

6; In a car lighting system, a headlight I circuit receiving energy from a variable source of supply, variable resistance regulating means in series with the circuit for maintaining a predetermined constant current in the circuit, operating means comprising mechanical means tending constantly to decrease the resistance and electric means tending to increase the resistance of the regulating means with an increase of current in the circuit connected in the circuit and in series with said regulating means for controlling the latter, a headlight in the circuit, a normally interrupted resistance cir cuit, means arranged in the headlight circuit for cutting out the headlight and cutting in the resistance circuit in series with the operating means thereby to maintain the nor mal resistance of the headlight circuit, a car light circuit connected to the resistance means, a plurality of lamps in the car light circuit, a protective resistance connected to the car light circuit, and means controlled by the current flowing through the headlight circuit "for connecting said protective resist ance in series with the lamps simultaneously with the collapse of the headlight circuit.

7. In a car lighting system, a headlight circuit receiving energy from a variable source of supply and adapted to operate with a constant current, variable resistance regulating means in series with the circuit, mechanical means tending through pressure to decrease the resistance oi the regulating means, electrically operated means responsive to current fluctuations connected in series with the regulating means for control ling the latter by varying the pressure of the mechanical means to maintain the current in the headlight cricuit constant irrespective of voltage fluctuation in the source of supply, a headlight in the circuit, means for maintaining the resistance of the headlight circuit constant when the light is broken, and a car light circuit connected to and reeciving energy through the regulating means and maintained constant by the current flowing through the headlight circuit.

8. In a car lighting system, a car light circuit receiving energy from a variable source of supply and operating with a constant current, a plurality of lamps in the circuit, a protective resistance in a normal open circuit connected to the car light circuit and adapted to be automatically connected in series with the lamps, a headlight circuit connected in parallel with the car light circuit, operating means connected in the headlight circuit and comprising mechanically and electrically controlled mechanism opposing each other with a rise of current and assisting each other with a fall of current in the headlight circuit, a variable resistance regulating means connected in series with the operating means and co-operat ing with the controlling means to maintain a constant current in both circuits irrespective of voltage fluctuation in the source of supply, and magnetically controlled means connected in the car light circuit and controlled by the current flowing through the headlight circuit for connecting said protective resistance in series with the lamps simul taneously with an abnormal decrease in flow of current through the headlight circuit.

In testimony whereof I allix my signature \VALTER W. HUNZICKER. 

